package org.apache.maven.project.harness;

/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *
 *  http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 * KIND, either express or implied.  See the License for the
 * specific language governing permissions and limitations
 * under the License.
 */

import java.util.ArrayList;
import java.util.LinkedHashMap;
import java.util.List;
import java.util.Map;

import org.apache.commons.jxpath.ri.QName;
import org.apache.commons.jxpath.ri.model.NodeIterator;
import org.apache.commons.jxpath.ri.model.NodePointer;
import org.codehaus.plexus.util.xml.Xpp3Dom;

/**
 * An attribute iterator for JXPath to support <code>Xpp3Dom</code>.
 * 
 * @author Benjamin Bentmann
 */
class Xpp3DomAttributeIterator implements NodeIterator {

  private NodePointer parent;

  private Xpp3Dom node;

  private List<Map.Entry<String, String>> attributes;

  private Map.Entry<String, String> attribute;

  private int position;

  public Xpp3DomAttributeIterator(NodePointer parent, QName qname) {
    this.parent = parent;
    this.node = (Xpp3Dom) parent.getNode();

    Map<String, String> map = new LinkedHashMap<String, String>();
    for (String name : this.node.getAttributeNames()) {
      if (name.equals(qname.getName()) || "*".equals(qname.getName())) {
        String value = this.node.getAttribute(name);
        map.put(name, value);
      }
    }
    this.attributes = new ArrayList<Map.Entry<String, String>>(map.entrySet());
  }

  public NodePointer getNodePointer() {
    if (position == 0) {
      setPosition(1);
    }
    return (attribute == null) ? null : new Xpp3DomAttributePointer(parent, attribute);
  }

  public int getPosition() {
    return position;
  }

  public boolean setPosition(int position) {
    this.position = position;
    attribute = (position > 0 && position <= attributes.size()) ? attributes.get(position - 1) : null;
    return attribute != null;
  }

}
